Image retention (also called burn-in when it is permanent) happens when an image gets imprinted on screen after being displayed for an extended period. Once the image retention occurs, you will notice it after a change of content or input. After a change of content, the imprinted image will appear as a faint remnant, visible through the new content. As an example, this is most obvious when elements from a video game such as life meters are still visible on top of a TV show after playing a video game for a long period. This is really more an issue for people playing video games, using their TV as a PC monitor, or watching sports and 24-hour news channels due to static banners or logos. This test only concerns temporary image retention which disappears over the course of a few minutes, however, we are also performing a long-term burn-in test which you can see the current status of here.
When testing for image retention we take photos at predetermined times, to analyze the amount of the original image that gets retained after being displayed for a specific time.
The image retention test is relevant when some parts of the screen are static, like when playing video games, using the TV as a PC monitor or using the TV as a display during an office meeting. It is also important when watching long sporting events or news coverage due to static graphics. It tends not to be a problem for people who only watch normal TV shows or movies since in those cases it is very rare to have a static image displayed on the screen for an extended amount of time.
It takes a while of displaying a static image before image retention begins to be visible, so depending on your use it may not be noticeable. This is why it is usually going to be gamers or PC users who experience it the most as they often have parts of the screen that are static, like a progress bar or the start menu from a PC. While the static image is being displayed the retention won't be visible, as it is only when changing content such as watching a movie that the image retention is going to be noticed.
Our image retention test video is made to test the resistance of the TV panel to image retention. It is made up of 3 different specific scenes:
To evaluate the image retention and stay consistent across all TVs, we adjust the backlight on the 15% gray scene to 2 cd/m², with the TV at calibration settings and with any local dimming features disabled. We play the video and take pictures of each 15% gray scene.
To determine the amount of image retention, we compare our reference image taken before the static logos with pictures taken after the 10-minute burn-in scene. These recovery photos are taken at 2-minute intervals, to provide an idea of the amount of image retention over time. We can then determine how much image retention is left.
TVs which continue to display image retention after a longer period of time (such as 10 minutes) generally present more of an issue, as the retention continues throughout normal content. This is worse than a TV which recovers quickly.
Not all TVs suffer from image retention. Here is the information about the different type of TVs:
In any case, whatever the type of TV, image retention is usually not a permanent problem but more a temporary annoyance.